This research project will include the study of several aspects of cell-associated and humoral tumor immunity in acute leukemia. In addition, it involves the extraction, purification, and characterization of tumor antigens in acute leukemia. We will develop a multifaceted approach to the study of cell-associated tumor immunity in leukemia patients. Four tests will be used concurrently, including in vitro lymphocyte blastogenic response, in vitro generation of macrophage migration inhibitory factor, in vitro investigation of lymphocyte cytotoxicity, and in vivo delayed hypersensitivity reactivity to both autologous leukemia cells and salt-extracted soluble antigen. The overall objectives of these tumor immunity studies include the evaluation and quantitation of the various cell-mediated components of tumor immunity in leukemia in order to determine why disease progresses or regresses in the face of apparent tumor immunity. In addition, we propose to evaluate the relationship between tumor immunity and prognosis and evaluate the effects of chemotherapy and immunotherapy on these various aspects of cellular immunity. Finally, this approach should more clearly define the interrelationships between cell- associated and humoral tumor immunity in acute leukemia. The extraction, purification, and characterization of tumor antigens in acute leukemia will provide important material for the study of specific cell-associated tumor immunity and also provide material for improved methods of immunodiagnosis and specific immunotherapy in leukemia patients. The development of rabbit antileukemia antisera will lead to improved immunodiagnostic tools in acute leukemia.